Sara Fahad Almatrafi, Mazin Mohammed Aljabri
Unilateral laterothoracic exanthema is a self-limited disease that occurs most commonly in children. It is characterized by unilateral exanthema, often in axillary region. The etiology is unknown but a viral agent is suspected. We report a 9-year-old girl with unilateral laterothoracic exanthema that occur during corona virus pandemic SARSCoV-2. The disorder was first described in 1962 and the term “Unilateral Laterothoracic Exanthema” (ULTE) was introduced in 1992. It occurs most commonly in toddlers and preschool aged children with an age range of 6 months to 10 years, male: female ratio is 1: 2. The etiology of ULTE remains unknown viral etiology have been suggested and screening for multiple viruses (e.g. EBV, CMV, HHV-6, HHV-7) was performed, no etiologic agent has been consistently demonstrated. A relationship to infection with Spiro plasma, parvovirus B19, and EBV has been noted in individual cases. Seasonal pattern has been described, occurring more frequently in winter or spring time. Usually preceded by a prodromal upper respiratory or gastrointestinal upset, and is characterized by unilateral and localized exanthema, often in the axillary region, that spreads in a centrifugal pattern, sometimes involving the contralateral side. The mucous membranes, face, palms, and soles are generally spared. The eruption lasts 4 to 6 weeks, exceptionally more than 8 weeks, and transient dryness or minimal post inflammatory hyperpigmentation of the skin subsides. Mild local lymphadenopathy has been found in about 50% of cases. A skin biopsy is usually not helpful, since histopathological examination discloses only nonspecific superficial dermatitis features, such as perivascular and periappendageal lymphocytic infiltrate, mononuclear cell exocytosis, spongiosis, and lichened dermatitis with parakeratosis.